Technical Field
The instant disclosure relates to a bicycle frame and, more particularly, to an electric bicycle frame.
Related Art
The main structure of a bicycle includes a frame, a driving system, a front wheel, and a rear wheel. Power supply of the driving system of a conventional bicycle purely depends on man. In other words, a rider has to tread pedals to drive the rear wheel to rotate via gear wheels and a chain in order to have the bicycle moved. The frame can be analogous to the skeleton of a human body. Varied components are affixed to the frame to complete a bicycle. In the realm of conventional bicycles, the design of frames emphasizes mechanical strengths and properties.
A kind of electric bicycles is commercially available, which allows a rider who rides the electric bicycle to save more labor. The electric bicycles can not only be driven by treading pedals but also be selectively driven by motors. For example, a rider may easily get tired and even exhausts physical strength such that he cannot keep riding anymore when climbing by the conventional bicycle. If a rider climbs by riding an electric bicycle, it is helpful that the motor outputs auxiliary power for driving the bicycle to assist the rider in climbing. As a result, electric bicycle riders not only save time and labor but also have fun in terms of riding a bike.
The electric bicycle, as the name implies, is required electric power to drive the motor. The main issue regarding the design of the electric bicycle is the power source. The electric bicycles at present adopt batteries as the power source. The battery is installed on the frame. The common design is to increase the tube diameter of the down tube or the seat tube of the frame of the electric bicycle so that the battery can be installed in the down tube or the seat tube. The down tube or the seat tube utilized for receiving the battery is usually made in a manner of aluminum extrusion. An aluminum extrusion tube has continuously identical cross-sections; therefore, the appearance of the tube is dull and is hard to satisfy the aesthetic criteria. The configuration of the battery installing in the down tube or the seat tube is unfavorable to the rider since he has to put the battery in or take the battery out of the down tube or the seat tube. Thus, the installation and detachment of the battery is inconvenient. In addition, the design of the battery has another issue regarding waterproof performance since the electric bicycle is for outdoor use.